Studies in cryo-immunology. IV. Antibody development in rabbits after iso-immunization followed by freezing.

Data presented in this report indicate that freezing of male accessory tissue in rabbits which have been previously sensitized by injection of saline extracts of rabbit male accessory glands material, elicits the formation almost exclusively of the IgG class of immunoglobulin and constitutes, therefore, a booster type of antigenic stimulation in these animals. It is suggested that the marked decrease in antibody activity shown by most of the iso-immunized rabbits following freezing of their male accessory tissue could be attributed to immune complex formation between the circulating antibodies and an autoantigen that may be released as a result of the cryo-immunization. An alternative explanation for the decrease in antibody activity is that the antibodies complex with the homologous autoantigen which is fixed but exposed in the freeze damaged tissue. The possibility that the antigenicity of antigen—antibody complexes may be a factor in the abrupt increase in antibody titre, from the minimum level at the 3rd or 4th day to a peak at the 7th or 8th day after cryo-immunization, is discussed.